Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux-2.6
[linux-2.6] / arch / x86 / power / cpu_32.c
1 /*
2  * Suspend support specific for i386.
3  *
4  * Distribute under GPLv2
5  *
6  * Copyright (c) 2002 Pavel Machek <pavel@suse.cz>
7  * Copyright (c) 2001 Patrick Mochel <mochel@osdl.org>
8  */
9
10 #include <linux/module.h>
11 #include <linux/suspend.h>
12 #include <asm/mtrr.h>
13 #include <asm/mce.h>
14
15 static struct saved_context saved_context;
16
17 unsigned long saved_context_ebx;
18 unsigned long saved_context_esp, saved_context_ebp;
19 unsigned long saved_context_esi, saved_context_edi;
20 unsigned long saved_context_eflags;
21
22 static void __save_processor_state(struct saved_context *ctxt)
23 {
24         mtrr_save_fixed_ranges(NULL);
25         kernel_fpu_begin();
26
27         /*
28          * descriptor tables
29          */
30         store_gdt(&ctxt->gdt);
31         store_idt(&ctxt->idt);
32         store_tr(ctxt->tr);
33
34         /*
35          * segment registers
36          */
37         savesegment(es, ctxt->es);
38         savesegment(fs, ctxt->fs);
39         savesegment(gs, ctxt->gs);
40         savesegment(ss, ctxt->ss);
41
42         /*
43          * control registers
44          */
45         ctxt->cr0 = read_cr0();
46         ctxt->cr2 = read_cr2();
47         ctxt->cr3 = read_cr3();
48         ctxt->cr4 = read_cr4();
49 }
50
51 /* Needed by apm.c */
52 void save_processor_state(void)
53 {
54         __save_processor_state(&saved_context);
55 }
56 EXPORT_SYMBOL(save_processor_state);
57
58 static void do_fpu_end(void)
59 {
60         /*
61          * Restore FPU regs if necessary.
62          */
63         kernel_fpu_end();
64 }
65
66 static void fix_processor_context(void)
67 {
68         int cpu = smp_processor_id();
69         struct tss_struct *t = &per_cpu(init_tss, cpu);
70
71         set_tss_desc(cpu, t);   /*
72                                  * This just modifies memory; should not be
73                                  * necessary. But... This is necessary, because
74                                  * 386 hardware has concept of busy TSS or some
75                                  * similar stupidity.
76                                  */
77
78         load_TR_desc();                         /* This does ltr */
79         load_LDT(&current->active_mm->context); /* This does lldt */
80
81         /*
82          * Now maybe reload the debug registers
83          */
84         if (current->thread.debugreg7) {
85                 set_debugreg(current->thread.debugreg0, 0);
86                 set_debugreg(current->thread.debugreg1, 1);
87                 set_debugreg(current->thread.debugreg2, 2);
88                 set_debugreg(current->thread.debugreg3, 3);
89                 /* no 4 and 5 */
90                 set_debugreg(current->thread.debugreg6, 6);
91                 set_debugreg(current->thread.debugreg7, 7);
92         }
93
94 }
95
96 static void __restore_processor_state(struct saved_context *ctxt)
97 {
98         /*
99          * control registers
100          */
101         write_cr4(ctxt->cr4);
102         write_cr3(ctxt->cr3);
103         write_cr2(ctxt->cr2);
104         write_cr0(ctxt->cr0);
105
106         /*
107          * now restore the descriptor tables to their proper values
108          * ltr is done i fix_processor_context().
109          */
110         load_gdt(&ctxt->gdt);
111         load_idt(&ctxt->idt);
112
113         /*
114          * segment registers
115          */
116         loadsegment(es, ctxt->es);
117         loadsegment(fs, ctxt->fs);
118         loadsegment(gs, ctxt->gs);
119         loadsegment(ss, ctxt->ss);
120
121         /*
122          * sysenter MSRs
123          */
124         if (boot_cpu_has(X86_FEATURE_SEP))
125                 enable_sep_cpu();
126
127         fix_processor_context();
128         do_fpu_end();
129         mtrr_ap_init();
130         mcheck_init(&boot_cpu_data);
131 }
132
133 /* Needed by apm.c */
134 void restore_processor_state(void)
135 {
136         __restore_processor_state(&saved_context);
137 }
138 EXPORT_SYMBOL(restore_processor_state);